Shoe with insole as part sole filler and method of making same

ABSTRACT

A method of manufacture of footwear and the footwear comprising the steps of providing a last with an upper thereon, providing a mold insert on the bottom of the last, providing a mold having a mold cavity for a tread sole, disposing the last and upper against the mold with the mold insert disposed within the mold cavity, forming a sole in the mold cavity having a depression therein in the shape of the mold insert, providing an insole with a first portion in the shape of the depression and a second portion substantially in the shape of the sole and securing the first portion of the insole in the depression. The tread sole and insole are formed of materials preferably having different physical properties. The tread sole can include one of tongues and grooves and the insole would then have the other of tongues and grooves, said tongues and grooves mating with each other. The step of providing an insole can include removing the mold insert from the mold cavity, disposing the last spaced from the tread sole and then forming the insole in the cavity formed by the removal of the weight relief and the spacing of the last from the tread sole.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a shoe having a sole filler provided in partby an insole and a method of making the shoe.

2. Brief Description of the Prior Art

In the manufacture of footwear, it is known to mold soles of rubber,polyvinyl chloride (PVC), polyurethane or other elastomers eitherdirectly to the shoe upper or to a welt which has been stitched to theshoe upper. Typical examples of such prior art is set forth in thepatents of Auberry et al. U.S. Pat. Nos. 3,965,517 and 3,758,903. Whilefootwear of the type set forth in the above-mentioned prior art operatesin satisfactory manner for the purposes intended, when a rigid sole isrequired, the sole tends to be heavy, relatively hard and does notprovide good thermal insulation. On the other hand, when rigidity is notrequired properties other than those inherent in rigid soles is desired,foamed soles have been utilized. However, the prior art has not providedthe combination of sole rigidity with sole softness or cushioning, lightweight and good thermal insulation properties.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a sole andmethod of making same which can provide the rigidity of the prior artrigid soles and still provide the other above noted desirable propertiesnot inherent in rigid soles.

Briefly, in accordance with the present invention, there is provided ashoe having an upper and a sole secured to the upper, either directly orthrough a welt, which is preferably rigid; though it can have anydesired properties, with a hollow sole interior section into which issecured a premolded insole of a material having the desired properties,preferably a relatively soft foam which provides cushioning, lightweight and thermal insulation. The insole is secured to the sole bymeans of adhesive, such as an epoxy, or by mating members in the soleand insole, such as a tongue and groove, the tongue preferably being aportion of the insole and the groove being premolded into the sole. Thetongue and groove insole embodiment can be made easily removable for thepurpose of, for example, drying, airing or cleaning thereof.

The shoe with sole in accordance with the present invention isfabricated by placing an upper on a last in standard manner, placing amold insert in the shape of the hollow sole interior section on the lastbottom, the mold insert preferably being a permanent part of the lastbottom, bringing the sole plate or mold for the sole and the last withupper thereon together in standard manner and then forming the sole inthe sole plate. The sole will adhere to the welt or the upper as in theprior art. However, there will be a cavity in the sole in the shape ofthe weight relief, this cavity being the hollow sole interior section.The sole will also contain grooves in the event the insole is to bemated therewith.

An insole is preferably premolded and is preferably of a materialdifferent from that of the sole. This insole has a bottom portion whichis the same shape as the hollow sole interior section and fits therein,the remaining portion of the insole lying above the sole and restingthereover. After removal of the upper from the last with mold insert,the insole is secured to the sole either by an adhesive, preferably anepoxy, or by tongues formed in the bottom portion thereof which matewith the grooves in the sole, thereby providing a removable insole. Ofcourse, the tongues and grooves can be reversed.

As an alternative, the mold insert can be removed from the last afterformation of the sole and a second material can be inserted into thehollow sole interior section. In this case, the last without the moldinsert and the sole form the mold cavity for the second material.

The sole is formed from any of the known prior art moldable solematerials, all of which are well known. Preferable sole materials arethermoplastic materials, preferably PVC, and rubber. Preferable insolematerials are foams, preferably polyurethane and other blown materials.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a molding last with mold insert in accordancewith the present invention;

FIG. 2 is a side view, partially in elevation and partially in section,of a molding last with upper in position for having sold directly moldedto the upper in accordance with the present invention;

FIG. 3 is a side elevational view of a shoe after removal from themolding last with a cavity in the tread sole within the shoe;

FIG. 4 is a side view of a molded insole for use in accordance with thepresent invention; and

FIG. 5 is a side elevational view of a shoe in accordance with thepresent invention with insole/sole filler disposed in and over the treadsole.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIG. 1, there is shown a standard molding last 1having a mold insert 3 secured thereto. The mold insert 3 is shaped toprovide the hollow tread sole interior section to be discussedhereinbelow. A shoe upper 5, with or without a welt secured thereto, isdisposed over the molding last 1 with mold insert 3, as shown in FIG. 2,and the last is mechanically held in place against the sole frame,within which the sole plate 7 is moved upward to its proper positionwith the upper 5 or welt (not shown) in contact with the upper edge ofthe sole frame. The material from which the tread sole 11 is formed isthen entered into the hollow cavity of the sole plate between the soleplate and the mold insert 3 to form the tread sole 11. Everythingdiscussed to this point is done in standard manner with the exception ofthe use of the mold insert 3.

The upper 5 is then removed from the molding last 1 and mold insert 3.At his time, the tread sole 11 is secured to the upper 5, eitherdirectly or via a welt, and the cavity 13 wherein the mold insert 3 wasdisposed during molding of the tread sole is now hollow, this cavitybeing the hollow sole interior section and shown in FIG. 3. Groovesand/or tongues are optionally disposed in the tread sole 11 if the moldinsert 3 contained finger or groove portions to accommodate formationthereof during the tread sole molding step.

An insole is then disposed in the hollow sole interior section. Inaccordance with one embodiment of the invention, as shown in FIG. 4, theinsole 15 is separately molded and includes a lower portion 17 which hassubstantially the same shape as the cavity 13 and an upper portion 19which preferably rests over the entire upper surface of the tread sole11. The insole 15 is secured to the tread sole 11 by an adhesive,preferably an epoxy, and/or by mating of tongue and groove members, ifpresent, or just inserted.

In accordance with another embodiment of the invention, after removal ofthe upper from the molding last 1 and weight relief 3, the weight reliefis removed from the molding last and the molding last is replaced in theupper to its original position except for some displacement from thetread sole 11 to permit a section similar to the upper portion 19 to beformed. It is apparent that the space previously occupied by the moldinsert 3 is now a new cavity as well as the space between the tread sole11 and the molding last 1. Accordingly, in a second molding operation, asecond material, preferably a foam such as polyurethane, is inserted inthe newly formed cavity, the foam adhering to the tread sole 11 withinthe cavity 13 and also being disposed over the entire sole tread.

The end result of either of the above described procedures is a shoehaving an upper 5, a tread sole 11 and a separate insole 15 secured tothe tread sole and extending thereover as shown in FIG. 5. The insole 15can be permanently affixed to the tread sole 11, such as with an epoxy,or can be removable therefrom, such as with the use of the tongue andgroove members, as discussed hereinabove ot just inserted.

Though the invention has been described with respect to specificpreferred embodiments thereof, many variations and modifications willimmediately become apparent to those skilled in the art. It is thereforethe intention that the appended claims be interpreted as broadly aspossible in view of the prior art to include all such variations andmodifications.

1-14. (canceled)
 15. Footwear comprising: (a) a tread sole having a toeregion at one end thereof and a heel region at an opposing end thereofand an upper secured to said tread sole; (b) said tread sole including acavity therein extending continuously from said toe region and beneaththe ball of a wearer's foot to said heel region and beneath the wearer'sheel, and wherein said cavity in the heel region is of substantiallygreater depth than other portions of said cavity; and (c) an insole witha portion in the shape of said tread sole cavity, said insole portiondisposed in said cavity and extending continuously from said toe regionand beneath the ball of a wearer's foot to and beneath the wearer's heelto provide support under a wearer's heel.
 16. Footwear as recited inclaim 15 and wherein said insole includes a lip portion integraltherewith and external of said cavity over said tread sole.
 17. Footwearas recited in claim 15 and wherein said insole includes a contouredouter surface.